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646. 1 

Iliinoiij Institute 

of Technology 


AT 220 

Green, G. Vernon 
The production of potassium 
chloride and iodine from 

^uTAii;aIUM CHLoiiXDS AND iuiJTIIE FliO.V. oliJA ./KED 

p;vEb5 wrRD m 

G . Vt^'rU-':^ GRKKN _^ KAi:^T;D ;3 . JO HNSOU 
to the 
FaE3IJ.-:NT a nd i'\ 'iCU^:Tlc 
For tho D3gr otj of 

Hav ing C ompl '•^tcd tha Prcjaorib^d Q oucao^ 
of Study in 

am:,; I GAL ekgiu zx^^^ihg^ 


CHICAGO, IL 60616 


'^^'^^ ^f dc^^^i^^^ ^Ai/^i 








A, Introdvction. 
P. Object of our Thesis, 

C. Method of Procedure. 

(1). Analyls of thj ''.''fjed. 

(£), Analysis of th ? Ash. 

(5). : sthods of ^nalv'sesi, 

(4). Destructive '^Istlllaticn of the W ed. 

(5), Lixiviation of the Ash. 

(6). Fractional Cr:,stalllzaticn. 

(7). Analysis of the Crys als, 

(8). Treatnent of the llothev Liquoi* for Iodine. 

D. Tabulation, riiscuission and Interpretation of Results. 

(1). Atlantic Weed. 
(£), Pacific Weed - First Shipment. 
(6). Pacific ?7aed - Second Shirment. 
(4) . Ccmparlson of the Results. 
F, Conclusions. 

(1). Pesme* of !^ork done by Balch on Sea Weed, 
(2). Cor:' arison of cur Results with those 

obtained by Palch. 
(3). Connarcial Viewpoint of our Results, 


Gevaral ;f?:on3ratiGni5 aro the saa was the principal 
source of rotassiu'a chloride, and tiio unl:: source of 
lodiny. Thaaa const Ituants were pathsrsd. and storac up 
by the sea weed. In localities whore labor was cheap, 
and at a tir.e of yeai* .;hon there was rothin" olse -lo do, 
these vvaoct, ware harvoEted a^id treated for the above 
constituente. The mothods us'^d in oxtractlnr these substan- 
ces were crude, unscientific and wasteful, ^.'ith the 
developnient of the Strassfurt deposits and the Chili 
saltpeter beds, sea v/eed was abandonee as a egu c3 of 
potassiun and iodine. 

The Gtraesfurt derosits furnish potassiun 
chloride of about 80^ purity; tha Chill saltpeter bads, 
v,'hich are th:- world's principal source of iodine, are 
rapidly nearin" depletion, F"a water contain:; O.O'*^ by 
weirht of potassivm chloridey it also contains a ti-i.cG of 
iodine. It haii lonr b^en known that cor ain varietlot. of 
S'3a weod contiiln pota;£Siu:ri chloride in a hi^h stats of 
purity. In order to obtain cl^-J^nically puru potaasium 
chloride from the I'orraan deposita, a laborious process of 
fractional c-ystallization is involved, A conaic<jratlon 
of these facts raises the (.uestion, " ^y not dep3nd upon 

the di/rcjstivr fi^nctions of t .c s.^a wo;iG for thr; ui'Lflca- 
tion of this salt, und v;.:y not laako the Icdln-a content of 
the viee6 pay for the r.anufacturp of tlie salt". 

With these queBtlcns in mind ./a obtain-id a 
eami'le of E~a v.a :d fror. th? Atlantic Oc an and two saaplfls 
frora the Pacific. Ou.-' the si e onbodios th3 oxporl::! jntaJL 
treatment of the^e wo^ds for their potaBSium chloride 
and iodine content. 

To datormlna (1) the yutuBBlum and iodine 
contsnt of vai-louG eeu weeds, (2) what products are 
obtained by tho dsctrvctive distillation of tlie weeds and 
(3) to ascertttln whothnr or not the tr-.atm^nt of the wearf 
for these products v.'oi!ld bo a coni.n rcial eucceeB, 
The various wejds v;ere analyjiod fort 
(1) . !"oisturo, 
(£). Volatile Matt sr, and 
(o). Ash. 
The ash v;as then lixlvlatad with .atar, nc. the 
watsr extract was evaporatad to crynei:.6 and the residue 
welf5;hed. Th3 residue was analysed for its various: constit- 
uents. A second saiaplo of w^od was lixiviateo .vith 
boilini^ wator m\d the extract evjipcr'atsd to di'yness and 
weighed. This residue tallied cl(ji:ely with th?? residue 
obtain'."'-" fi-on wator li:>iviation of the ash. The rGi;ldue 
of ash enaininr* aftar ertraction with wa.ei*, .^as dissolved 
in lij^dro chloric acid and th^ various constituents determin- 
ed. There yet regained a residue from th^: hydrochloric 
acid extraction. This was wsi.phad as silica. 

Iron and alumina aece precipitator.' by aLiaonia; 
the hydroxides obtained v/ere Ijpaalted and woifrhec as coia- 

bined oxides. Calclvin was deternilnQcl as oxalate and weif»h- 
ed the oxide, Magnealvin vas weighed as the pyrophosphate. 
Sulphates were determined by preclT-ltatlon with barium 
chloride. Carbonates were titrated with standard hydro- 
chloric acid. Chlorides were titrated wltli standard silver 
nitrate, usinjp; potassiua chrociate as an indicator. Carbon- 
ates were first decon osed witli nitric acid. Sodlun 
arsenate as an indicator n;ave excessively high results in 
the titration of chlorides and had to be rejected as 
an indiccitcr. IVe were unable to determine the ccnblned 
halides by the Jannasch nethod; neither were we able to 
detemine iodine by titration with potassiun permangan- 
ate. Organic Impurities pave too high x'alues for t le iodine, 

ISq finally used colorlmetric methods for the 
estimation of iodlno and bromine. In detail the.. e methods 
are as followsi 
For iodinet- 

To a aliquot part of the solution containing 
the iodides, add an equal amount of sulphuric acid ( 50fy 
n2S04- 50^ H30 ), Then add bromine v/ater ( .2 cc, Br. in 
20 CO. ^TCl and made up to one liter) drop by drop until 
maximum coloration Is produced. This rouctlcn was carried 
on in a rrreuluated tube such as is used for detemlnlng 
carbon by color. Five cc. standard solution potassivim 
Iodide containing 0.001 grams iodine per cc. was treated 
In another tube with the seuae reagents. The color of the 


two BolutionB was made the sane by dilution with, dlstlll- 
Gd water. The ratic between the volumeti In the two tubes 
was read off arjl thj amounte of iodine ir. '-he unknown 
sanple calculated. 

The :nethod of procedure was the sane as for 
Iodine, save that Instead of brcmins .vater an excosB of 
saturated solution of cixLorlne water was used to displace 
the bromine, Ti\e standard solution for conparlson con- 
tained 0,001 ^rans of bromine per cc. An JXcesB of chlorine 
water was added to fom Iodine chloride, thereby destroy- 
ing the color produced by iodine, Tliese aethods are usod 
(according to Thorpe) for the rapid estimation of iodine 
in sea weed ash, Tho method for Icc-ina in aaid to be 
▼ery accurate, Tlio iodine in the mother liquors from the 
crystallization of the salts in the weed, was doteiTOlned 
by this nothod, owing to the fact that the volumos of 
liquor were too siaall for dlBtlllation add sublimation, 

The woedB *are destructivoly distilled in a c ;pp«r 
rotort and tho products of decomposition were condensed 
and caught in suitable receivors,V^ater was added to, 
each charge of T.:3-!d to facilitate distillation. The 
residue in the still was black ov/lrr» to incomplete burn- 
ing of the carbon. As it was im^ osslbje to produce « 
white or ivon gray ash in the retort, the blac': rosidue 

was removed and heated In an open iron pan, Tlie resxilt 
was a ^ray asli, it beinr Imposalble to produce a white 
aeh without fuslnjf» the i:iaterlal. We conducted a current 
of air thru the retort in hopes of oxidizln" all the 
carbon, but tho ash obtained was not as rray as tlidt 
produced by heutin^ in an open iron pan where it was 
possible to constantly stir the ash. Had the retort 
baen provided with a mechanical stirrer, the method no 
doubt would hav-? b en successfvil. It was essential that 
the residue from the retort be heatod still i.ior? strongly, 
because the ivater extract froa it was of a reddish- brown 

The ash was lixiviated with bolllnp water for 
one hour. Two more extractions with bollin^ v.'ater were 
made, each of one half hour duration. The extract* after 
coQbinlnr aiid f ilterln/^ to rer.ove suspendud natter were 
concentrated to a point of crystallization. The first 
crop of crystals was recrysallized and the mother liquor 
was addod to the original nother liquor. Two r:ore 
crops of crystalB were obtained from this liquor. The 
final r-'iOther liquor was treated for iodine. A qualitative 
analysis was made of each crop of crystals and each con- 
stituent was t::en do tormina a quantitativaly, 

We examined three samples of we-ac" th3 first 
cane from the Atlantic Ocoan, the other two from the 
Pacific, re will now separately discuss each w«ed. 

Tills W9ed, calloci eoa praas, was pathox^od at 
fjrcanport L, I, ITov/ York In ^loventjor lUlO.It gro\/s upon 
rocks and In ehallow «auer. It Is conplouoly sutaei-^ed 
at dJ.1 'ulTuQe, Rcu/rh vveuthei^ tears the \«eed from the; rocXs 
aiid casts it v.pcn the shore. Thorpe in his "Dictlonax^y 
of Applied Cliomistry" states that tlils species contains 
no Iodine. Our analysis of I'n-- ^e}d is as followst 
Moisture 15,86^ 

Ash 31.06 

Volatile natter 55.08 

P. C. ash water soluble 34.57 

Vater sol, niatter in weed 6.64 

Silica 9.26 

CaCOj 13.04 

AlgOs and Fe^Og 1.54 

MgS04 2.54 

NaCl 0.07 

KCl 3.40 

Iodine trace 

Bromine 0.075 

The ash obtained frcia this weed was white and 
feathery. An inspection of the analysis will show that 
the weed is high in calcium carbonate a d silica, while 
it is low in pota3si\;a anc sodiuia chloride. .'e account foe* 

the presence of ineolublv'; calclun car-hcnate by t>o f aou 
that it inai" have existed ir tl:c weed as the bicarbonate, 
7.11311 an aquecuE ertrucl of tho ash was boiled a. precip- 
itate of ctJ.civ:.i carb>..nd, a settled oi;t. For the :r.ost y^art 
th3 constituents of t:-:it> ..oed aro Insoluble in watox^, 
We ware unable to detect any iodine Ina praa Sctf.iyle of 
the, Tiiia apj)arentl: bcjtrs out tho a'-^cve etatment 
made by Thorpe, 

Yle found that it would bo lupciiGiblJ to obtain 
the inorganic constituents of this -rfood or any of the 
other r/s3ds by a sinplo water extraction. The ovfeaaic 
impurities were extr^ictod by the water in sufficient 
quantity to inpart to the residue a blackish-brown color, 
Neither would filtration thru bone-char, nor i^^niti^n effect 
a complete renoval of crpanlc natter from "cho salt residue. 
The reaoval of organic mattsr by i;-nitiGn had the adaed 
objection in that tho salt was fused and parti: volatil- 
ized. It is th-:jr:^fcre evident that it ia best to Ifmite 
the we3d to ae white an ash as is vossible without 
fusion, and then to extract the soluble na ter with hot 
water. By neans we v/e.'O able to eecure a clsar. white 
Bait. This sane may be said repardinr; the two othor veods 
upon which d6ter;::inations were aade. 

On th3 following pape will bn fcvnd the data 
concernin;? the experimental treatnent of the *eed. 


Wel/^ht of v.'a^e takon 3.00'f 

Taight of ash ottainod 1.84 

T^eight of distillate & Vol. matter 1.16 

Percent aiJli 61.305^ 

The \-'2rce^t ach is al.'.:oct doi;bl3 the trus 
valv.9 owing to Its ii'CCuplete oxidation in tha retort. 
Ft. of ash lixiviated O.o5# 

^ KCl in asli 3.40 is equal to 0.0119=f 

Wt. of cr: istals obtained 0,01 

Analysis of the CrvBtalsi 

K2SO, 25. sr.^ 

CaCO^ 12.81 

Ua.SO 9.73 

FCl 4^.18 equals 0.00'*4# 

l)aCl 6.12 

Porcsnt yield of XCl 37.00^, 

The results show t:.'a,t thero wiir> a v r^' ■poor 
7lGld of crystals. Tn fact th97y' could scarcely be called 
crystals as thsir appearancs rssenbled that of a coarae 
powder. On att9rtptin;=r to dissolve t;i3 crystals for ra- 
cr;>'stallizaticn it was fou.nd that tlie;" \*3rn difficultly 
Soluble in hot water and alr.ost insoluble in cold water, 
Attenpta to s'^curo thre? crops of crystals Hnv^ futile. 

'I^ilo wo <'v'>i'o \vnaMo tc fine! any lodlnu In 
a one m'ttp eaDpl^ cf the ueIi, an approolablo a;.( v.nt wao 
aetimatod In iho cothor llijuor fron Uin cryctola, '."e 
attribute this t>c Vaq fact that tlioro \siJLti a f^rjatQi' ccnc- 
-ntratlon In th-' .Motho:' liquor, thus j-:a'.:lnp It poociblo 
to <3etc5ct itt< proaonoe. 

rietlllatlen Produotis, 

'Vat or waa arjc", -to *c t}y: woed t.o aid In llo 
distillation. 'Iho (iiBtlllatlcn was of noeaatslry conduct- 
ed Blcarly, ovilnr* *,-■.: t;-.e fact that a rapid rlfsw in tss:^p- 
oratviro c«uu:'i a i^apld evolution of urcondaneable ;»a8aB, 
Iho firiit ccr.dQnaatffiB app^iax'oa at B'6 darrrossj C, Ihofss 
w4re small in aacimt, ThQ taapGratVii-o ro:i(i to i-b daproea 
whsro aoiit cf thy dlKtlliat'^B cazi? ovor. As tlxa ta-uporatiire 
roao above 100 oo/rrBaa tho ttiour.t of tarry r.attyr ocainr; 
over V<3caaa i?.wra •• ronounc&d. The ociot* of tr.-? dlstlllatja 
varlaci frua a paid yello.* at 100 darrsea to a bro'*nlah 
black at '6<i0 dofroea. Indicating an incroaue in ta ry 
tia'^'.or^ In th'i fraction coUgcm: at 120 dotrr«OB a 
faint odor of alcohol iat; notic^c^ but no at-.a^^ipt ^ao 
laaco tv.. roccvcji' It, In no cthor fr.*Owlon »&3 tl-./»r.J air.}: 
indication of th^ ■ raaonoo of olcvhcl, 

i'^ona of ihii ."aaot ovolv-'d durinr* th Cia -illat- 
ion ft"ar-j i'ich onourh to burn. I'iifi a'^atunent alsu aprllaa 
to ths two Pacific Wf»or.ti, 








98 C. 





































Data on tho Distillation Products. 

Pale Yellow 
Red tinge 

llo sharp clianpo in color, 
color /gradually became 
darker due to increaeeln 


tarry natter. 
Very dark owin," to 
increase in tar, very 
small anoints. 
Thert* distillatas were aci^^d to forra three 
portions, ill lht3 following nannerj 

First Portion 05 to 110 C. 

Second Portion 110 tc 200 

Third Portion 200 to aeo. 

An att.e-.ipt was made to f r:i/5t Icnate the above portions, 
but a vory surprisin!^ result was obtaired - practically 
all of each .rtion cane ov-ar at 98 detrreoe. In 
case th=?r3 remained behind a snail anount of coke. We 
explain this behavior of the distillatesby tiio fact that 
water was beinr continually for^.-.ed thruout the distilla- 
tion of the weed. Part of this water was due to th3 origin- 
al moisturo in the ::-.aterial and '^art to the fomation of 

water by ths cc.'bustlon c^ the hydrofen aiic uxyrren In. 
the we.^d. 

Tir ■^iRST ?Aci-^ic T:^^r. 

this wsed, Imo 11 as Fereocy.itiB I.f?T'.tl:3ana, was 
pathorad in Decenbor 1910, free Decc>ptlyn Pass, an 
arm of Pu^at Soujid. It v;as rrowlnr In water about sixty 
fe:t ds'-^p. Tha -ijiiod consists of a lon^ ston varying in 
dianotsr from on 3 to six inches at t is top, and taperint^ 
to a c'^ia'aster' of a fraction of an inch at ths other ax- 
troniity. The shape of tho Bi-sm resenbloe tha.t of a caiu'c^. 
The tcp of tho s" on: teiTninatas In an aii^ blaccer which 
serves to float it. The leaves raciiato frcn tlile blacdar 
and flcbit upon tho '..a.t t. This firet samplo consisted 
of s'-e:jE only. It wai: rQcel"""^f^ in Chica";o by ox^res^i a 
few 6j.yB after bainr '^ath3i:8C-, and was lnuasdiatoly dried 
in an oven. Beforo drying there were no salts visible on 
the Eton, but after c'r-in.'^ the?; aj'pj'ar'^d in proat abund- 
ance. The anovnt of sfflorescod salts v/as uo great that 
It fall off in Kcales. 

An analysis of th--^ wa'-5d followsi 
''olsture l.QH^. 

Ash 58.40 

\^olatil3 :.-fttter £;&.78 

"'atsr sclubla ash ^S.-iO 


Vrat;?r sol. lujitter In woed 60.45^. 

Silica 0.30 

Al.O , f: FevO^ 1.09 

CaCO^ 2.53 

MgS04 1.95 

Bronlne 0.l;7 

Iodine 0,26 

ITaCl a, 01 

KCl 52.71 

An inspection of tho analysis will show 
that this wioC is hif»h in an aah which is for thJ most 
part aolubla in iT»atar; that it lu high in votiiesium 
ciilcride, and low In calcium carbonate and silica; that 
the br-omina content is sli,p;htly in excess of the iodine. 
The ash of t].ls w83c had a stronf^ tondancy to ftise upon 
Ignition and it *vae Inpcssitle to obtain better than a 
dark g-ni!' aah. T^'xveriiaental data concoimin.r^ the treat- 
ment of thJ ':';9t;d in ae followsi 

Weight of *'99d taken 0,62!f 

reight of ash obtained 0.40 

V/eight of cletillats arc Vol. natter '^,22 

Percent ash j4,50 

The a~:iount of (distillate co.-uinr' cr^r ^'as 
very saall acaounting to 0,09=*. For the r^ost lart it 
consisted of tar. The 0,11^ of volatile .:iatter was non- 

combustible -aatoriul. 

Ft. of ash liiciviatod 0.069?# 

f^ KCl In the *6h -- 77.5iJ"' -- e'^ualB 0.066 

Wt. Of crystalr first crop 0,075 

Wt. of crystals sacond crop 0.005 

Analysis of the Crystjils 

First Crop 
Water 4.5R<^ 

K.^SO, 4.66 

KCl 89.16 is oq\ial to 0.0o2b4 

NaCl 1.15 

Second Crop 
'ater 1.56''< 

K^SO^ 11. F, 5 

T^ri 63.59 18 oqual to 0.0042# 

Tctal r*^! In th" crystals 0.0<j7J? 

Porcert ylelc of the rci = C.067/ 0.0(38 » 9r-!.7'^ 

Th.e firnt crop of cr''*st'ilr v.^jf; character^ z-^d 
by tho lar.c3 a-^-jrrt, and thoir hlfh purity \n potaet^lum 
chloride. To difficulty waij GrT:'f?riorc^d g-ltJior in obtain- 
Int' elthor tho first or second crop. ITie tj.3ccnd and 
thlrfl crops were conMned ovtln," to the sttoII amour t cf 
tho latt.;r, This cor-hined crcn was Inf^'cior to f.'.e first 
In pirity, owlnr to tho presence of aulnhutes. 

The distillaticn products ..are wutrsr Jind tar 


which cane over at 125 de;»roes C, to 360, V!e vjqcq vinabla 
to find any other constltuants in tho distillates. 

The Seconfl Pacific ^eed. 

This weed is of f.a same sp cIgs as Vao previous 
one. It ivas gather i^d thray uonths l.itsr from tho tame 
locality. The sample rscelved consisted cf stems, bladders, 
and laavos, and had h^sn oven drl-'d previous to ship- 
ment, Tho analysis of tlio w^^d is as folio v/s: 





Volatile V 



Water soluble ash 


Watex' sol. 

natter in 

the weefj 




AIhO, c: Fe 









lodi 9 


Brom ln« 






An Inspection of the analysis will sho* that 


the nolsture ccntent is hirhor; that the ash, /ater sol- 

uMe aeh, calciun carbonate, mapneslun svilphato. Iodine, 

and alkali chlorides arj louver than in th^' cus^i of the 

first sacipla of this sane weed. 

Experinental data ccncorninr the tr.-j.'itiner.t of 

this *e3C is as follows: 

WeifJit of wa3d ta':on 3.00-^ 

Wel.uht of the ash 2.15 

?:«lght of the distillate 0.53 

Weight of the vol at 11 ? natter 0.32 

Percent ash 71.06^^ 

This does not rap.-o ont the truo voluo of tlie ash owing 

to incomplete oxidation in the retort. 

?7t. of ash lixlvlat d 0.70# 

fc KCl in the a-h -- 75,05^ — - 0.52 

Wt of crystals rirst Crop 0.21 

Wt. of crystals Second Crop 0.14 

Wt. of crystals Third Crop 0.04 

Analysis of the Crystals. 
First Crop 
Water 12.34^ 

KgSO^ 3.62 

KCl 81,48 equals 0.1714 

NaCl 1.99 

Second Crop 
Water 7,705o 





70,63 equa" s 












7'6,^'>Z ev\xstlB 








Total t:' 


f^ yield 



- 0. 



,52 - 


Threo crops of crystals were obtained from 
lixiviation of the ash frcn this wecjd. The potasslun 
chloride content dec-eatjcs with each succeedlnF' crop 
of crystals v.hile tha asnount. of potassivm sulphate and 
soditua chloride Increuijss, Tills is to he OMpoc:. -d from 
the fact that the ■ urer crystals blvo found i-i tho first 
crystallization. The larger crop wab obialn'o at firsti 
tho second crop acici-nted to t u thirds that of the firstj 
while th;' las', aciountec to almost nothing. 

The distillation of t is weed .as conducted in 
the S£ nannsr as In the ca^^e of the previous w eds, Tlae 
character of the distillates was for th) most pai^t watery, 
A snail a-riount of tar floated on the surface of V\e distil- 
atas in patches, Owlnp to t};e snail volume anci r ature of 
the products no attempt v;as nade to fractionate then, 


It was UT'On this weed that we nade th'.? unsucce.sful 
attempt to oxidize the ash by blowin'^ alx" thru th retort. 

Comp«u:*lson of the Experimental Results. 

In only ens of thes3 wesds, nsoaely the Atlantic, 
do our analyses shew th ) truenolstur; content. This 
weed v/as dried upon tho rocks In t,h3 sun. In ho c -se of 
*.he Pacific weec's the uoistures were c'btain^d after the 
samples had b^on previously dried in cA'-ens. According 
to Raich 1&^: Is a fair moisture content for aun dried 
weed. This sana e^uthor states that about 90^' of the 
freshly gathered weed ie water. 

This cnstttuent is lowest in the Atlantic 
weed, which re ?e to show that t'lls srecies is a poor 
collector of mineral :.:atter. The t'.o Pacific saaples 
contained 68 and 42'^ of ash respectively. Inasmuch as 
these weeds are of the sunie srecies and cane frou the 
same locality, it would seen that their rjineral content 
is influenced by thra.^ factors, viz.: 

(1). Season of the y:;ar, 
{£), Age of the weed, and 
(3), Part of weod tal^on for analysis. 
The Pacific we .ds v.'ero ratho.-ed at different seasons of 
the year, one in December, and the othex- in the natly spring 













Again, one w«'3d nar l^ave been •.In cld.?r In which 'iv nt 
it would bo .v.uch r-lcher Ir. Baits, due to t\o f jtct that 
the longer the weed crrows the TGator Its etor^^ cf uineral 
matter bee mes. This prirtlcular spocles reaches maturity 
in twelve tc fifteen nonths, at tho end of hlch tine 
It dies. Further, tho ^ art of tu8 weod ta':;jn for analysis 
doubtless has a bearlnrt upon tho rasults obtain g. The 
first sanpl? of Pacific we:^d conslstsc? of storns only, 
the second conslstod of stems, bladders and laavos. 

The potaeelura chloride contont inc. eases with 
the percent of ash. '"ron cur results it ivoulc appoiir that 
the stems of the wacd asslxillate th? larf-est amount of 
potaseium salts. 


It is "evident from our results thi.t some weeds 
do not rat'.ior an;: iodine. As in tlio casa with potassium 
chloride, the steus of th 5 Pacific v/ead gathered the largr 
est amount of iodine. Our results seem to show that 
a high silica, aluiuina, iron, calcium and aapnesium content 
is to be accompanied b" small aiiounts of ] otasi^iua and 
iodine. As nay be expected from what has e^Lread:' bean 
stated, the first Pacific -.veod yieldt- tho urest and 
larrest araount of 7cta;8lii^. cbJLuride, llie lou- yield of 
potassium cliloride (59^* ) obtalmo from t:'ie second Pacific 
weed, nay bi explain^-d by th t f ict that th'3 oxidatl n of 


th3 ash in an open pan causad tho material to fU63. 
This rendered a runplets extraction of • otassiviin salts 
impossible , We ar3 at a luss tc account for th'^ lev 
yi«ld (i57<) of potassium clilorldo from th^ Atlantic 
weed. This weed yields a hiphar percnnt of sodium ctxlorlde 
and potaesiiua sulphati? than do the Pacific weeds. 

The species of sea wood, known as sea fraes, 
which cans from thR Atlantic, it; far- infai'lor in svei'y 
respect to tho ;riant ?<olp of the Pacific; and tli ■ staas 
of the f^lant kolp ar-e a richar sov.rco of potassliim and 
iodine than are all th" party of thJ sane weed taken 
as a whole. 

RNrxIN^"RI?!r'r CH^riGTRY, Dec, 1909. 

In "brief, "r. "alch conducted his investigations 
as follcv/ss- 

Comparatlv8 analyses ware nado of different spec la. of 
weed which ware collected at different stapjss of devolop- 
aant, -'is analyses may to classified undor thesa headinpai 
(l) . Effloresced salts which fell av/ajr from thJ 

entire we jd durlnp the course of dryin;t», 
(2) . Youni? w ;ad8, 


(3) I'ature weadB, 

(4) Stems, 

(5) Bladders, and 
(U) Leav s, 

A comparatlva uumnary of the work dene by Palch 
and thj work don^ by ourselves is found on the attached 
blue-print. Inasmuch as this thesis is concerned with 
ths potassii^m chlorid3 and iodino content alone, we 
include thet-e two constituents only in .he comparative 

An inspection of the table will show that 
our analysis of th9 weed Nereocyatis L«utkoana tLgrenB 
fairly closely with th-i-t nade by Balch, it beingi- 
KCl 5:3.71^ vs. o5.10f^ 
I 0,23^ vs. 0.24^ 

It would harcl;.' be fair to ccripare our results 
on ths second Pacific woed with zIichq obtained by Palch 
ov/lnt^ to tLe fact that cur anal:.S9S are on t'ls basis of 
ths whcle weed whilo those of the former are upon the 
varioue parts of t le waad. 

It is at cnce evident that the invetti rat ions 
conducted by Palch and ourselvas upon the Pacific .■»;> .ds 
laave no room for doubt as to tlie superiority of these 
weeds over the sample obtained ''rom th3- Atlantic. 

Raich and urs^lvss apree clceely upon t}i3 r.ot- 


■ J. .■ I' 

^ « « 


aselum chloride contant of Liio crystallized aalj. 
obtained from the L>t9ni6 of tho Pacific we?d. Palch 
fotind double tho amount of Iodine that we doternlned in 
the ssae w ;..>d. Here it Is evldant that tlio iodine content 
of a w 'd is affected by tho season of th^ year r.i v/hlch 
it wat; p-atherad anc by its are, because -ve kncv/ that 
the sanples in question were patherod at diff .^I'ent 
seasons and it is safe to venture that they wer3 not In 
the suRc stags of devalopaent, 


Our data eiiows that in a ton of the dry stems 
of tho Pacif c wasd there is approximately a half ton 
of potacGluE clilcrlde whose ■ urlty Is 89f'>, The present 
market value of t:ils sail of a liks purity is about .$4i3,00 
pjr ton. A ton of the s,ii;:.e ws .c containi: four poundt of 
lodino, the valuo of v/..Lch is about '2,00 p^r pound. This 
fflves th3 sterns th3 follov/inp valuet 

Potassiuifl Chloride ^21.00 

Iodine 8.00 

Total value ^29.00 

The analysis of tha :second Pacific wced^ which 
repretents th? avera.^e contents of all t}ie parts, shov/s, 
that a ton of the dry nat'^rial contains about dOO ounds 
potassium chloride of BOf- purity. Accord Inr to nai'ket 


.f sports tills salt is worth about ht40,00 pe.' ten. Uj on 
thla taels a ton of t.vj whole w.od, 1. a. all i-ai'ts 
Included, hue the followin'^ valuo!- 

Potasclun Cnloi'ido, 600/" $1^3.00 

Iodine, 2^ ^±.00 

Total Value v.lG.OC 

In cui' exparinonts -./o fcund t .o distillation products 
of all throa weods to ho worthJLsss. 

'Thlle tlie s-:3ns cf Uae Pacific wjod represent 
a valuG of "28,00 per ton. It must bo :■ Jiuaaboi-od that 
it would bi:- raoro ccstly to treat stuns alone than it 
would to treat the ontiro weed. In order to fst stems the 
entiro weed ;aust be gathfirod, a^.d the niarkct value of 
the salts obtained from a ton of dry weed is but half 
that of thot;a obtainod from a ton of dried sLens, 

:'.:r, ^alch states that a ton of tiioroly air 
dried kelp should be v,ort}: about v2o,00. lie aliio saya that 
\-h'i volatile and non- volatile distillation jjroducts are 
valuable, lie doss not, however, tell what constituents are 
in the distillation products, neithei- dooo he ^iw- .-i us 
where L-iey could be ...iirkottd and v;hat their valut; woiild 

'"e find tliau a ton of the; Pacific we 3d has but 
60^ of the valu.^ ectinated Vy i^alch. his doct, not take 
account of the fj^t that he asuipniS a valuj to ti. : cistll- 
lation products #hil ■■ wj do not. '"e know r.othirr a^. to the 

cost of rBLtiiorlnr and tr.^ 'tinf* this weed, but we do 
'•now that nox-e nuut tr. paid for connon labor In tha 
Pacific States than in Chicago,, th3 market for 
thG rrcducts cifijiuf acturod frun the v.-acc is closer to 
New York than to the ■Pacific Rtatos. This wcv.ld :..oan 
that a lov/or freipht rate coulc b .? off red by New York 
jobbsre who are Belllnr thv aaao products, 

''alch states that the po*.aBsium chloride obtained 
by him has a purity hiph enough to neet th ^ L-oquireraants 
of a chemically pv.-e articlG, This 'vas true only in the 
case of t:.3 efflorescod salts which fell fron the dried 

Vq beliove that neither Palch nor ourselves 
possess 8i;fficlon-^ data regard Inp .markets and cost of 
production to justify us in saylri-' that tlio treatment of 
Pacific voeds v/ould b? a ccrr.:orcial eucccss. The i:pecie8 
of Atlantic i^eoc exaEir.?d, c vlnr tc l\& low [ otaesium 
contont anc lii-ck of iedire, is not to b-: considered as 
a coiE.:; •- 016,1 propositicn. 

vJe are Latisfiad that to obtain any klrd of 
a yield cf iod r.e uj^on an experimental seal- would necess- 
itate the troatment of a r.uch larmier ar.'unt of w^od than 
was UBOd in thlt: investiration. 

In ccnclvslcn '.vc ca: that, ■.,'hil--' cur rf?r\lt6 
ar3 not very proiuiEint»,^lt v/ould ■.•oil be v,-':rth the while 


to furth'^r I'^vestirate fhe Trcssit^illtl 3t; cf tho Pacific 
weed. Py a fv.rth'^r i?:v9stj "^atlon v' .:-ar. ey^srla^r I Lnp 
v.pon a ^cr3 c mprehe-HKive scale. It Is £;uid that the Bolld 
portion c^' thi stem, v.'hlf'h tcws 'jo'A'n ne«,r ^ he recks, 
contains 'by far nore iodlno than any other -art of the 
weed. It wc ulf^ be interestln" to r^o -vt in a tv* boat and 
fine; out what difficulties woulc t^ encountered In cutting 
this weed off clos? tc the rocks, and -/hat sort of u 
contrivance would bo required for fettinr th9 harvoBtf'd 
weed to shore. Tliis r'ata, surpleraen^. ec. by a nci'o thoro 
Invastlpatlon *-Lan our ovm, wAuld plve a pood idea atj to 
v/hether tho weed mi;»ht bo tr atod for itb ]:ctast;lULa 
salts and iodine on a coranercial scale.